Use-after-free in Linux kernel - CVE-2026-98742

Vulnerability identifier: #VU157090

CSH Severity: Low

CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98742

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service by triggering a kernel use-after-free.

The vulnerability exists due to missing synchronization leading to a use-after-free in the ALSA sequencer compatibility port-info ioctl handler when processing concurrent port-creation requests. A local user can issue concurrent compat CREATE_PORT requests to bypass the port-count check, cause port indices to wrap to an existing address, and trigger access to a freed subscriber during subsequent teardown to potentially cause a kernel crash.

Linux kernel
SUSE Linux Micro
SUSE Linux Micro Extras
kernel-default
kernel-64kb
kernel-64kb-debugsource
kernel-64kb-devel
kernel-default-devel
kernel-syms
kernel-obs-build
kernel-obs-build-debugsource
kernel-default-debugsource
kernel-default-devel-debuginfo

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-default - update to 6.4.0-159998.55.1
kernel-64kb - update to 6.4.0-159998.55.1
kernel-64kb-debugsource - update to 6.4.0-159998.55.1
kernel-64kb-devel - update to 6.4.0-159998.55.1
kernel-default-devel - update to 6.4.0-159998.55.1
kernel-syms - update to 6.4.0-159998.55.1
kernel-obs-build - update to 6.4.0-159998.55.1
kernel-obs-build-debugsource - update to 6.4.0-159998.55.1
kernel-default-debugsource - update to 6.4.0-159998.55.1
kernel-default-devel-debuginfo - update to 6.4.0-159998.55.1

• https://git.kernel.org/stable/c/2db234e163f0d211b69a4eebbec8aacc5a54a80e
• https://git.kernel.org/stable/c/413211dd31cb2ef2fc99fb0aa1a037a97509502c
• https://git.kernel.org/stable/c/702d92f361f65d9698c473c7599d471395dc4341
• https://git.kernel.org/stable/c/95b2e0361c88753afa030c10698be0a1a5b67650
• https://git.kernel.org/stable/c/fc5c52848e405b6efb073db5035bb9ebaed11ec4

• Use-after-free in Linux kernel core seq
• SUSE update for the Linux Kernel